Oil Pressure Alarm Chirping ?

While pulling into my slip yesterday at the end of a two hour motoring trip that (thanks to zero wind), my oil pressure alarm “chirped”. This only happened at idle while in gear.

With all lines fast and with the engine still running, I put it in gear, revved the engine a little and the chirping stopped. Then back to idle, in gear same chirp. I put the boat in neutral and no alarm chirp at idle?

I use the word “chirping” because the buzzer sounds a solid tone with the ignition on before starting the engine. This was a very slight, intermittent buzz.

I checked the oil before starting the day (as always) and it was spot on.

Any ideas in what it could be? A bad sender maybe? A loose ground?

Thanks for your input!
Rick

Where is everyone around here?

You have temporarily stumped the peanut gallery.

ZHowever, to be helpful, when that happened to me I poured out my drink and just started over from scratch.

The problem turned out to be soap in the glass.

There is some discussion over on the Indigo Electronics site about how temperature effects oil pressure, under different use scenarios, at least for the Atomic 4. Their claim is that due to these effects the oil pressure cannot be set correctly for both short runs and extended cruising. Unless, of course, you purchase their oil heater/cooler heat exchanger. I'm almost sold on it, in light of extended cruising up and down the big river. But not quite. Their theory states that on extended cruise, the oil gets too hot and oil pressure will be too low.

Alternatively, is it possible that there is more than one sensor connected to the buzzer? e.g. temperature or water-flow? When the impellers are reaching the end of their lifetime, I get that sort of chirp from the buzzer at idle due to low water flow/high temp. Running the engine a bit faster increases the flow. Of course, that would work for oil, too.

Could be a bad sender. This happened to me with my Yanmar 3GM30F - I only got the buzzing at idle (neutral or engaged), disappearing with a little throttle. However, I had recently relocated the sender to accommodate an additional sender for an oil pressure gauge, and I think the move may have damaged it. Whatever the case, replacing it was cheap and fixed the issue.

Do you have an oil pressure gauge in your cluster? If not, I would plumb in a pressure gauge and monitor the pressure when the alarm goes off.

Thank you all.

The buzzer can mean trouble. Hopefully it is only the sender.

The water pump was recently upgraded so water flow shouldn’t be an issue.

Now, about that that soap in the glass.......:nerd: they call that waste at the Elks Lodge!

You've really got three possibilities:

1. The sender itself is defective
2. Your oil is thinning too much when heated by long running (try a heavier grade of oil)
3. Your oil pump is worn. When the clearances grow between the vanes and the pump body you lose oil pressure.

Revving the engine temporarily solves all of these, so doesn't help you much for diagnostics.

Good Luck!

Kevin Wright
E35 Hydro Therapy

Kevin A Wright said:

You've really got three possibilities:

1. The sender itself is defective
2. Your oil is thinning too much when heated by long running (try a heavier grade of oil)
3. Your oil pump is worn. When the clearances grow between the vanes and the pump body you lose oil pressure.

Revving the engine temporarily solves all of these, so doesn't help you much for diagnostics.

Good Luck!

Kevin Wright
E35 Hydro Therapy

Click to expand...

All good points. But also, oil pressure comes mostly from the main bearings. So it could be worn pump, or worn main bearings as well. Hopefully just the sender is bad. I guess a clogged oil filter could also cause this. Check oil filter too. Would be rare someone had an oil filter clogged, but I guess it could fail in some way. Anything is possible with a machine.

I had very similar problem during long cruise last week on my E35-2 with a Universal 20hp. I checked everything possible and concluded that sender had gone bad. Signal to alarm buzzer was constant, so I ended up disconnecting the alarm buzzer to get back home. In the course of this, I discovered that prior owner had already disconnected the temp alarm wiring from alarm buzzer. Made it back with no incident but having both senders checked now.

Funny after being being on this thread I was down doing my engine maintenance on Saturday. Got done changing the tranny oil and heat exchanger zinc and started her up for the first time in probably 2 months. No warning buzzer when I turned on the power, and when running it 'chirped' randomly. Didn't have time to follow up before I left for the day.
Got down there at lunch to day figuring I'd have to get a new sender, but found that I'd pulled the light blue wire off the sender while fussing with the heat exchanger. Glad I checked before ordering a new one.

Kevin Wright
E35 Hydro Therapy